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We study systems of two and three mesons composed of pions and kaons at maximal isospin using four CLS ensembles with $a\approx 0.063\;$fm, including one with approximately physical quark masses. Using the stochastic Laplacian-Heaviside method, we determine the energy spectrum of these systems including many levels in different momentum frames and irreducible representations. Using the relativistic two- and three-body finite-volume formalism, we constrain the two and three-meson K matrices, including not only the leading $s$ wave, but also $p$ and $d$ waves. By solving the three-body integral equations, we determine, for the first time, the physical-point scattering amplitudes for $3\pi^+$, $3K^+$, $\pi^+\pi^+ K^+$ and $K^+ K^+ \pi^+$ systems. These are determined for total angular momentum $J^P=0^-$, $1^+$, and $2^-$. We also obtain accurate results for $2\pi^+$, $\pi^+ K^+$, and $2K^+$ phase shifts. We compare our results to Chiral Perturbation Theory, and to phenomenological fits., Comment: 61 pages, 33 figures, 37 tables

We use lattice QCD calculations of the finite-volume spectra of systems of two and three mesons to determine, for the first time, three-particle scattering amplitudes with physical quark masses. Our results are for combinations of $\pi^+$ and $K^+$, at a lattice spacing $a=0.063\;$fm, and in the isospin-symmetric limit. We also obtain accurate results for maximal-isospin two-meson amplitudes, with those for $\pi^+ K^+$ and $2K^+$ being the first determinations at the physical point. Dense lattice spectra are obtained using the stochastic Laplacian-Heaviside method, and the analysis leading to scattering amplitudes is done using the relativistic finite-volume formalism. Results are compared to chiral perturbation theory and to phenomenological fits to experimental data, finding good agreement., Comment: 7 pages, 4 figures, 2 tables. v2: typos and refs

Recent imaging experiments show a surprisingly robust regime of liquid-solid phase coexistence in a 2D electron system near the quantum melting/freezing transition, with the two phases mixed in mesoscopic domains. Strikingly, the experiments find no noticeable difference in electron density between the liquid and solid domains, which is at odds with both microemulsion scenarios and scenarios in which phase coexistence is driven by fluctuations of a long-ranged disorder potential. Here, we show that such phase coexistence without density difference can be induced by random fluctuations of a short-ranged disorder potential. We further show that disorder tends to stabilize the Wigner Crystal phase to higher densities, which is also consistent with the experiments., Comment: 5+2 pages, 3 figures

When navigating and interacting in challenging environments where sensory information is imperfect and incomplete, robots must make decisions that account for these shortcomings. We propose a novel method for quantifying and representing such perceptual uncertainty in 3D reconstruction through occupancy uncertainty estimation. We develop a framework to incorporate it into grasp selection for autonomous manipulation in underwater environments. Instead of treating each measurement equally when deciding which location to grasp from, we present a framework that propagates uncertainty inherent in the multi-view reconstruction process into the grasp selection. We evaluate our method with both simulated and the real world data, showing that by accounting for uncertainty, the grasp selection becomes robust against partial and noisy measurements. Code will be made available at https://onurbagoren.github.io/PUGS/, Comment: 8 pages, 4 figures Accepted to International Conference on Robotics and Automation (ICRA) 2024

Monitored many-body systems can exhibit a phase transition between entangling and disentangling dynamical phases by tuning the strength of measurements made on the system as it evolves. This phenomenon is called the measurement-induced phase transition (MIPT). Understanding the properties of the MIPT is a prominent challenge for both theory and experiment at the intersection of many-body physics and quantum information. Realizing the MIPT experimentally is particularly challenging due to the postselection problem, which demands a number of experimental realizations that grows exponentially with the number of measurements made during the dynamics. Proposed approaches that circumvent the postselection problem typically rely on a classical decoding process that infers the final state based on the measurement record. But the complexity of this classical process generally also grows exponentially with the system size unless the dynamics is restricted to a fine-tuned set of unitary operators. In this work we overcome these difficulties. We construct a tree-shaped quantum circuit whose nodes are Haar-random unitary operators followed by weak measurements of tunable strength. For these circuits, we show that the MIPT can be detected without postselection using only a simple classical decoding process whose complexity grows linearly with the number of qubits. Our protocol exploits the recursive structure of tree circuits, which also enables a complete theoretical description of the MIPT, including an exact solution for its critical point and scaling behavior. We experimentally realize the MIPT on Quantinuum's H1-1 trapped-ion quantum computer and show that the experimental results are precisely described by theory. Our results close the gap between analytical theory and postselection-free experimental observation of the MIPT., Comment: 7 figures

Josephson junctions are the principal circuit element in numerous superconducting quantum information devices and can be readily integrated into large-scale electronics. However, device integration at the wafer scale necessarily depends on having a reliable, high-fidelity, and high-yield fabrication method for creating Josephson junctions. When creating Al/AlOx based superconducting qubits, the standard Josephson junction fabrication method relies on a sub-micron suspended resist bridge, known as a Dolan bridge, which tends to be particularly fragile and can often times fracture during the resist development process, ultimately resulting in device failure. In this work, we demonstrate a unique Josephson junction lithography mask design that incorporates stress-relief channels. Our simulation results show that the addition of stress-relief channels reduces the lateral stress in the Dolan bridge by more than 70% for all the bridge geometries investigated. In practice, our novel mask design significantly increased the survivability of the bridge during device processing, resulting in 100% yield for over 100 Josephson junctions fabricated.

We present recommendations for how to improve reproducibility in the field of condensed matter physics. This area of physics has consistently produced both fundamental insights into the functioning of matter as well as transformative inventions. Our recommendations result from a collaboration that includes researchers in academia and government laboratories, scientific journalists, legal professionals, representatives of publishers, professional societies, and other experts. The group met in person in May 2024 at a conference at the University of Pittsburgh to discuss the growing challenges related to research reproducibility in condensed matter physics. We discuss best practices and policies at all stages of the scientific process to safeguard the value condensed matter research brings to society. We look forward to comments and suggestions, especially regarding subfield-specific recommendations, and will incorporate them into the next version of the report.

Most students who begin at a community college do not complete their desired credential. Many former students fail to graduate due to various barriers rather than their academic performance. To encourage previously successful non-completers to re-enroll and eventually graduate, a growing number of community colleges have implemented re-enrollment campaigns focused on former students who have already made substantial progress toward graduation. In this study, we randomly assigned over 27,000 former community college students to a control group, "information-only" treatment group, or "information and one-course waiver" treatment group to examine whether re-enrollment campaigns can improve their likelihood of long-term persistence and credential completion. Although we showed in earlier work that the "information and one-course waiver" treatment had a positive impact on former students' likelihood of re-enrollment, our findings reveal the re-enrollment intervention has no effect on students' likelihood of long-term persistence or credential completion for the pooled sample or any subgroup of interest, including low-income students, racially minoritized students, or adult students. Simply put, this particular re-enrollment intervention including one-time, one-course tuition waivers increased former students' likelihood of re-enrollment but was not an effective lever to increase "long-term" academic outcomes among previously successful community college students who departed early without earning a credential.

In studying compensated semimetals, the two-band model has proven extremely useful to capture electrical conductivities with intuitive parameters of densities and mobilities of electron-like and hole-like carriers, as well as to predict their magnetic field dependence. Yet, it rarely offers practical insight into magneto-thermoelectric properties. Here, we report the field dependence of thermoelectric (TE) coefficients in a highly compensated semimetal NbSb$_2$, where we find the Seebeck ($S_{xx}$) and Nernst ($S_{xy}$) coefficients increase quadratically and linearly with field, respectively. Such field dependences were predicted by the semiclassical Boltzmann transport theory and the Mott relation of the two-band system, and they are realized when two conditions are simultaneously met [1]: the multiple of cyclotron frequency ($\omega_c$) and relaxation time ($\tau$) is much larger than one, $\omega_c\tau \gg 1$ and the tangent of Hall angle ($\theta_H$) is much smaller than one, $\tan\theta_H \ll 1$. We use the relation between two carrier densities $n_e$ (electron-like) and $n_h$ (hole-like) derived from the field dependence of the TE coefficients, to refine the two-band model fittings. The compensation factor ($\frac{|\Delta n|}{n_e}$, where $\Delta n = n_e-n_h$) is found two orders of magnitude smaller than what was found in the unrestricted fitting and hence the larger saturation field scale for magnetoresistance. Within the framework of the semiclassical theory, we deduce that the thermoelectric Hall angle $\tan\theta_{\gamma} = \frac{S_{xy}}{S_{xx}}$ can be expressed $\big(\frac{|\Delta n|}{n_e}\times \omega_c\tau\big)^{-1}$. Our findings offer crucial insights not only for identifying the empirical conditions for the field-induced enhancement of the TE performance but also for engineering efficient thermoelectric devices based on semimetallic materials., Comment: 8 pages, 4 figures

Photorealistic 3D scene reconstruction plays an important role in autonomous driving, enabling the generation of novel data from existing datasets to simulate safety-critical scenarios and expand training data without additional acquisition costs. Gaussian Splatting (GS) facilitates real-time, photorealistic rendering with an explicit 3D Gaussian representation of the scene, providing faster processing and more intuitive scene editing than the implicit Neural Radiance Fields (NeRFs). While extensive GS research has yielded promising advancements in autonomous driving applications, they overlook two critical aspects: First, existing methods mainly focus on low-speed and feature-rich urban scenes and ignore the fact that highway scenarios play a significant role in autonomous driving. Second, while LiDARs are commonplace in autonomous driving platforms, existing methods learn primarily from images and use LiDAR only for initial estimates or without precise sensor modeling, thus missing out on leveraging the rich depth information LiDAR offers and limiting the ability to synthesize LiDAR data. In this paper, we propose a novel GS method for dynamic scene synthesis and editing with improved scene reconstruction through LiDAR supervision and support for LiDAR rendering. Unlike prior works that are tested mostly on urban datasets, to the best of our knowledge, we are the first to focus on the more challenging and highly relevant highway scenes for autonomous driving, with sparse sensor views and monotone backgrounds. Visit our project page at: https://umautobots.github.io/lihi_gs

Mobile robots operating indoors must be prepared to navigate challenging scenes that contain transparent surfaces. This paper proposes a novel method for the fusion of acoustic and visual sensing modalities through implicit neural representations to enable dense reconstruction of transparent surfaces in indoor scenes. We propose a novel model that leverages generative latent optimization to learn an implicit representation of indoor scenes consisting of transparent surfaces. We demonstrate that we can query the implicit representation to enable volumetric rendering in image space or 3D geometry reconstruction (point clouds or mesh) with transparent surface prediction. We evaluate our method's effectiveness qualitatively and quantitatively on a new dataset collected using a custom, low-cost sensing platform featuring RGB-D cameras and ultrasonic sensors. Our method exhibits significant improvement over state-of-the-art for transparent surface reconstruction., Comment: https://umfieldrobotics.github.io/VAIR_site/

Radially extended disk winds could be the key to unlocking how protoplanetary disks accrete and how planets form and migrate. A distinctive characteristic is their nested morphology of velocity and chemistry. Here we report JWST/NIRSpec spectro-imaging of four young stars with edge-on disks in the Taurus star-forming region that demonstrate the ubiquity of this structure. In each source, a fast collimated jet traced by [Fe II] is nested inside a hollow cavity within wider lower-velocity H2 and, in one case, also CO ro-vibrational (v=1-0) emission. Furthermore, in one of our sources, ALMA CO(2-1) emission, paired with our NIRSpec images, reveals the nested wind structure extends further outward. This nested wind morphology strongly supports theoretical predictions for wind-driven accretion and underscores the need for theoretical work to assess the role of winds in the formation and evolution of planetary systems, Comment: This preprint has not undergone peer review or any post-submission improvements or corrections. The Version of Record of this article is published in Nature Astronomy and is available online at https://doi.org/10.1038/s41550-024-02385-7

Safe motion planning algorithms are necessary for deploying autonomous robots in unstructured environments. Motion plans must be safe to ensure that the robot does not harm humans or damage any nearby objects. Generating these motion plans in real-time is also important to ensure that the robot can adapt to sudden changes in its environment. Many trajectory optimization methods introduce heuristics that balance safety and real-time performance, potentially increasing the risk of the robot colliding with its environment. This paper addresses this challenge by proposing Conformalized Reachable Sets for Obstacle Avoidance With Spheres (CROWS). CROWS is a novel real-time, receding-horizon trajectory planner that generates probalistically-safe motion plans. Offline, CROWS learns a novel neural network-based representation of a spherebased reachable set that overapproximates the swept volume of the robot's motion. CROWS then uses conformal prediction to compute a confidence bound that provides a probabilistic safety guarantee on the learned reachable set. At runtime, CROWS performs trajectory optimization to select a trajectory that is probabilstically-guaranteed to be collision-free. We demonstrate that CROWS outperforms a variety of state-of-the-art methods in solving challenging motion planning tasks in cluttered environments while remaining collision-free. Code, data, and video demonstrations can be found at https://roahmlab.github.io/crows/, Comment: https://roahmlab.github.io/crows/

We study expansiveness properties of positive measure subsets of ergodic $\mathbb{Z}^d$-actions along two different types of structured subsets of $\mathbb{Z}^d$, namely, cyclic subgroups and images of integer polynomials. We prove quantitative expansiveness properties in both cases and strengthen combinatorial results obtained by Bj\"orklund and Fish in arXiv:2401.03724, and Bulinski and Fish in arXiv:2102.05862. Our methods unify and strengthen earlier approaches used in arXiv:2401.03724 and arXiv:2102.05862 and to our surprise, also yield a counterexample to a certain pinned variant of the polynomial Bogolyubov theorem.

High-definition (HD) maps provide environmental information for autonomous driving systems and are essential for safe planning. While existing methods with single-frame input achieve impressive performance for online vectorized HD map construction, they still struggle with complex scenarios and occlusions. We propose MemFusionMap, a novel temporal fusion model with enhanced temporal reasoning capabilities for online HD map construction. Specifically, we contribute a working memory fusion module that improves the model's memory capacity to reason across a history of frames. We also design a novel temporal overlap heatmap to explicitly inform the model about the temporal overlap information and vehicle trajectory in the Bird's Eye View space. By integrating these two designs, MemFusionMap significantly outperforms existing methods while also maintaining a versatile design for scalability. We conduct extensive evaluation on open-source benchmarks and demonstrate a maximum improvement of 5.4% in mAP over state-of-the-art methods. The project page for MemFusionMap is https://song-jingyu.github.io/MemFusionMap, Comment: Accepted to WACV 2025

Neural Radiance Fields and Gaussian Splatting have transformed the field of computer vision by enabling photo-realistic representation of complex scenes. Despite this success, they have seen only limited use in real-world robotics tasks such as trajectory optimization. Two key factors have contributed to this limited success. First, it is challenging to reason about collisions in radiance models. Second, it is difficult to perform inference of radiance models fast enough for real-time trajectory synthesis. This paper addresses these challenges by proposing SPLANNING, a risk-aware trajectory optimizer that operates in a Gaussian Splatting model. This paper first derives a method for rigorously upper-bounding the probability of collision between a robot and a radiance field. Second, this paper introduces a normalized reformulation of Gaussian Splatting that enables the efficient computation of the collision bound in a Gaussian Splat. Third, a method is presented to optimize trajectories while avoiding collisions with a scene represented by a Gaussian Splat. Experiments demonstrate that SPLANNING outperforms state-of-the-art methods in generating collision-free trajectories in highly cluttered environments. The proposed system is also tested on a real-world robot manipulator. A project page is available at https://roahmlab.github.io/splanning., Comment: First two authors contributed equally. Project Page: https://roahmlab.github.io/splanning

Let $E$ be an elliptic curve defined over $\mathbb{Q}$ with conductor $N$ and $p\nmid 2N$ a prime. Let $L$ be an imaginary quadratic field with $p$ split. We prove the existence of $p$-adic zeta element for $E$ over $L$, encoding two different $p$-adic $L$-functions associated to $E$ over $L$ via explicit reciprocity laws at the primes above $p$. We formulate a main conjecture for $E$ over $L$ in terms of the zeta element, mediating different main conjectures in which the $p$-adic $L$-functions appear, and prove some results toward them. The zeta element has various applications to the arithmetic of elliptic curves. This includes a proof of main conjecture for semistable elliptic curves $E$ over $\mathbb{Q}$ at supersingular primes $p$, as conjectured by Kobayashi in 2002. It leads to the $p$-part of the conjectural Birch and Swinnerton-Dyer (BSD) formula for such curves of analytic rank zero or one, and enables us to present the first infinite families of non-CM elliptic curves for which the BSD conjecture is true. We provide further evidence towards the BSD conjecture: new cases of $p$-converse to the Gross--Zagier and Kolyvagin theorem, and $p$-part of the BSD formula for ordinary primes $p$. Along the way, we give a proof of a conjecture of Perrin-Riou connecting Beilinson--Kato elements with rational points., Comment: A main result supersedes the preprint arXiv:1411.6352

We consider the motion of two massive particles along a straight line. A lighter particle bounces back and forth between a heavier particle and a stationary wall, with all collisions being ideally elastic. It is known that if the lighter particle moves much faster than the heavier one, and the kinetic energies of the particles are of the same order, then the product of the speed of the lighter particle and the distance between the heavier particle and the wall is an adiabatic invariant: its value remains approximately constant over a long period. We show that the value of this adiabatic invariant, calculated at the collisions of the lighter particle with the wall, is a constant of motion (i.e., {an exact adiabatic invariant}). On the other hand, the value of this adiabatic invariant at the collisions between the particles slowly linearly in time decays with each collision. The model we consider is a highly simplified version of the classical adiabatic piston problem, where the lighter particle represents a gas particle, and the heavier particle represents the piston., Comment: 6 pages

Multimodal large language models (LLMs) have achieved notable success across various domains, while research in the medical field has largely focused on unimodal images. Meanwhile, current general-domain multimodal models for videos still lack the capabilities to understand and engage in conversations about surgical videos. One major contributing factor is the absence of datasets in the surgical field. In this paper, we create a new dataset, Surg-QA, consisting of 102,000 surgical video-instruction pairs, the largest of its kind so far. To build such a dataset, we propose a novel two-stage question-answer generation pipeline with LLM to learn surgical knowledge in a structured manner from the publicly available surgical lecture videos. The pipeline breaks down the generation process into two stages to significantly reduce the task complexity, allowing us to use a more affordable, locally deployed open-source LLM than the premium paid LLM services. It also mitigates the risk of LLM hallucinations during question-answer generation, thereby enhancing the overall quality of the generated data. We further train LLaVA-Surg, a novel vision-language conversational assistant capable of answering open-ended questions about surgical videos, on this Surg-QA dataset, and conduct comprehensive evaluations on zero-shot surgical video question-answering tasks. We show that LLaVA-Surg significantly outperforms all previous general-domain models, demonstrating exceptional multimodal conversational skills in answering open-ended questions about surgical videos. We will release our code, model, and the instruction-tuning dataset.

Significant work has been done on advancing localization and mapping in underwater environments. Still, state-of-the-art methods are challenged by low-texture environments, which is common for underwater settings. This makes it difficult to use existing methods in diverse, real-world scenes. In this paper, we present TURTLMap, a novel solution that focuses on textureless underwater environments through a real-time localization and mapping method. We show that this method is low-cost, and capable of tracking the robot accurately, while constructing a dense map of a low-textured environment in real-time. We evaluate the proposed method using real-world data collected in an indoor water tank with a motion capture system and ground truth reference map. Qualitative and quantitative results validate the proposed system achieves accurate and robust localization and precise dense mapping, even when subject to wave conditions. The project page for TURTLMap is https://umfieldrobotics.github.io/TURTLMap., Comment: Accepted to IROS 2024

We construct split anti-cyclotomic Euler systems for Galois representations attached to certain RACSDC automorphic representations on the group $\mathrm{GL}_n\times\mathrm{GL}_{n+1}$. As a result, we make progress towards certain rank 1 cases of the Beilinson--Bloch--Kato conjecture for those representations., Comment: 25 pages

We prove an inverse of Furstenberg's correspondence principle stating that for all measure preserving systems $(X,\mu,T)$ and $A\subset X$ measurable there exists a set $E \subset \mathbb{N}$ such that \[ \mu\left( \bigcap_{i=1}^k T^{-n_i}A\right) = \lim_{N\to \infty} \frac{\left|\left( \bigcap_{i=1}^k (E-n_i) \right)\cap \{0,\dots,N-1\}\right|}{N}\] for all $k,n_1,\dots,n_k \in \mathbb{N}$. As a corollary we show that a set $R\subset \mathbb{N}$ is a set of nice recurrence if and only if it is nicely intersective. Together, the inverse of Furstenberg's correspondence principle and it's corollary partially answer two questions of Moreira.

Hydrodynamic transport effectively describes the collective dynamics of fluids with well-defined thermodynamic quantities. With enhanced electron-electron interactions at elevated temperatures, the collective behavior of electrons in graphene with minimal impurities can be depicted as a hydrodynamic flow of charges. In this new regime, the well-known rules of Ohmic transport based on a single electron picture no longer apply, necessitating the consideration of collective electron dynamics. In particular, the hydrodynamic analogues of Joule heating and thermal transport require consideration of the viscous motion of the electron fluid, which has a direct impact on energy dissipation and heat generation by the fluidic motion of charge. In this work, we probe graphene hydrodynamics with thermal transport and find two distinct, qualitative signatures: thermal conductivity suppression below the Wiedemann-Franz value and viscous heating leading to magnetically-induced redistribution of temperature. We find these two effects are coincident in temperature and density, providing robust qualitative signatures of hydrodynamics, despite arising from two distinct aspects of this new regime: microscopic momentum conservation due to electron-electron scattering, and geometry-dependent viscous dissipation. Our results mark the first observation of viscous electronic heating in an electron fluid, providing insight for thermal management in electronic hydrodynamic devices and offering a new methodology for identifying hydrodynamic states in other systems., Comment: 36 pages, 9 figures, including supplementary information

We report on the critical influence of small-scale flow structures (e.g., fronts, vortices, and waves) that immediately arise in hot-exoplanet atmosphere simulations initialized with a resting state. A hot, 1:1 spin-orbit synchronized Jupiter is used here as a clear example; but, the phenomenon is generic and important for any type of a hot synchronized planet -- gaseous, oceanic, or telluric. When the early-time structures are not captured in simulations (due to, e.g., poor resolution and/or too much dissipation), the flow behavior is markedly different at later times -- in an observationally significant way; for example, the flow at large-scale is smoother and much less dynamic. This results in the temperature field, and its corresponding thermal flux, to be incorrectly predicted in numerical simulations, even when the quantities are spatially averaged., Comment: 9 pages, 4 figures, submitted

We present new Chandra X-ray observations of TAP 26, a ~17 Myr old magnetically-active weak-lined T Tauri star that has been reported to host a massive planet in a 10.8 day orbit. At a separation of a = 0.097 AU the planet will be exposed to intense X-ray and UV radiation from the star. The first observation caught the star in a state of elevated X-ray emission with variability on a timescale of a few hours and an X-ray temperature kTx ~ 2 - 4 keV. Two subsequent observations 5-10 days later showed slow variability and a lower X-ray flux and temperature (kTx ~ 1 keV). We characterize the X-ray emission and estimate the X-ray ionization and heating rates that will need to be incorporated into realistic models of the planet's atmosphere., Comment: 12 pages, 2 tables, 3 figures

Let $E/\mathbb{Q}$ be an elliptic curve of conductor $N$, $p$ an odd prime of good ordinary reduction such that $E[p]$ is an irreducible $G_{\mathbb{Q}}$-module, and $K$ an imaginary quadratic field with all primes dividing $Np$ split. We prove Iwasawa Main Conjectures for the $\mathbb{Z}_p$-cyclotomic and $\mathbb{Z}_p$-anticyclotomic deformation of $E$ over $\mathbb{Q}$ and $K$ respectively, dispensing with any of the ramification hypotheses on $E[p]$ in previous works. Using base change, the proofs are based on Wan's divisibility towards a three-variable main conjecture for $E$ over a quartic CM field containing $K$. As an application, we prove cases of the two-variable main conjecture for $E$ over $K$. The one-variable main conjectures imply the $p$-part of the conjectural Birch and Swinnerton-Dyer formula if ${\rm ord}_{s=1}L(E,s)\leq 1$. They are also an ingredient in the proof of Kolyvagin's conjecture and its cyclotomic variant in our joint work with Grossi \cite{BCGS}.